The vast, dying landscapes in The Road are edged with flame, telling a story of the world unmade in stark images. While the design in this film is eloquent, its characters aren't. What lurks beneath their silence?

The Road, which opens today, is based on a bleak novel by Cormac McCarthy where a man and his son travel through a world destroyed by a vaguely-explained apocalypse that has covered the planet in a cloud that blocks the sunlight and kills all plant life. Brutal and horrific, it is a story difficult to adapt to film - especially a holiday film. And indeed, the movie has a troubled history for this very reason. Plagued by endless edits, its release was delayed an entire year: Rumor had it that nobody could figure out how to market the damned thing because it was just too grim.

Whatever that editorial tinkering did, it didn't tone down the grimness. The man known only as Papa, played with ragged intensity by Viggo Mortenson, has lost everything - his beautiful country home, his wife (Charlize Theron), and civilization itself. All he has left is his young son. Most of the movie is preoccupied with the awful, starvation-laced journey the two of them take, through dying forests and cannibal ranches, to the southern coast. They're looking for something better than certain death, trying to keep hope alive.

At the heart of every brilliant road movie are finely-drawn characters. The plot arc may be harnessed to their journey, but only as a way to express how the characters' relationships with the world change as they travel. Great road movies like Thelma and Louise or even Wizard of Oz use landscapes and pitstops to foreground human relationships. And that's where The Road falls flat.

Part of the problem with the father/son relationship in this movie is, to be fair, the actor who plays the boy (Kodi Smit-McPhee). Whiny and cutsey by turns, he looks like he belongs in a remake of Home Alone - not in a barren post-apocalypse eating bugs. More than that, though, the father's love for his boy is simply too exalted, too idealized, to be realistic or even interesting. At one point Papa and the boy share dinner with an old man by the side of the road, and Papa confesses to the man that the boy "is God" to him. The bloated symbolism in this comment masks a basic meaninglessness - the boy is holy, their family relationship is holy, and that drains all the essential human complexity from both of them.

It's fascinating to see the world become an empty vessel, but all The Road pours back into it are hollow truisms. Family is good. Sons are good. Fathers are protectors. There is even a dreadful product-placement scene where man and boy, on the verge of total starvation, find a giant cache of flagrantly branded food items in a bomb shelter. Here we learn that Vitamin Water is good. Cheetos are good. Jack Daniels is good. What's truly grim about this movie isn't imagining the fall of civilization, but instead imagining what would happen if everything in our society evaporated except for families and advertising.

We need desperately to have characters we can relate to in this world where most people have degenerated into cannibalism or worse. And yet there are very few moments in the film where we actually see any kind of realistic ambiguity or subtle characterization. There is one intriguing moment when Papa and boy are robbed while Papa is hunting for food and the boy is sleeping. When they find the robber, Papa forces him to strip and steals all his possessions - just as he did to them. Though Papa wants to teach his boy to be a "good person," we see that circumstances are forcing him to slide into desperate, unforgivable evil. This is also the only time when the boy acts like the preteen he is, violently disagreeing with what his father has done.

To succeed, The Road needed more scenes like this, where its characters break out of the dull molds of Papa Saint and Boy Angel. We needed to know more about why the man knows so much about anatomy and medicine (was he a doctor?), and what motivates him and his son beyond a nearly religious fervor to survive. And why, if they are journeying to the coast to find a better place to live, does the man never attempt to connect with non-dangerous people? The movie gives us a few possible answers to these questions (maybe Papa has gone crazy over the loss of his wife; maybe there are no non-dangerous people) but they are sloppily vague and leave our characters ill-defined throughout the film.

I don't want to make it seem like the problem with the movie is that the characters are minimalistic. There is an elegance to the idea that the need to survive pares everyone down to their most basic selves. But that's not what's going on in The Road. We're not getting minimalism so much as simplistic sentimentality. We learn that children are beautiful, perfect creatures; families are good; and evil is as easily-recognized as cannibalism. Papa and his son remain one-note throughout The Road; instead of developing, they wander from a blandly dismal scenario into a blandly mawkish one.

As I said earlier, the one consistently breathtaking aspect of this film is the landscape where it is set. Father and son walk through grey, empty spaces full of ashy buildings, abandoned trucks, and greenery reduced to sticks. We've seen post-apocalyptic cities done well before, but The Road's true visual genius lies in its majestic substantiation of total environmental collapse. One way the movie is different from the book is that we're fairly sure that the apocalypse was caused by a meteor crashing to Earth (Papa says there was a rumble) - and it's tossed up enough dust to shut out the sunlight. We witness what would happen to Earth's ecosystem without sunlight. Vegetation has become tinder, animals have wasted away, and the only food left is in cans or on the bodies of surviving humans.

What this also means (weirdly) is this stately art movie is echoing the disaster scenario from blow-em-up apocalypse flick 2012. Given the cliched smarminess at the heart of The Road, however, the comparison is all too apt.